Carbonitriding treatment has been known as measures for improving durability of a bearing component included in a rolling bearing (see, for example, PTD 1 (Japanese Patent Laying-Open No. 2007-277648) and PTD 2 (Japanese Patent Laying-Open No. 2008-267402)). The carbonitriding treatment is heat treatment in which steel is heated to a temperature not lower than an A1 transformation point for diffusion and penetration of carbon and nitrogen into steel and thereafter is quenched. The carbonitriding treatment is effective for extending scratched contact life which is important performance of the rolling bearing.